Macmillan Dictionary offers a unique treatment of metaphor, showing how many ordinary familiar words and phrases have metaphorical meanings. The dictionary has over 60 unique features on metaphor, called Metaphor Boxes, to help you reach a deeper understanding.

Dr Rosamund Moon, an expert in the field of metaphor, wrote this article and the Metaphor Boxes in Macmillan Dictionary.


Metaphor is prevalent in English and other languages. People often consider it a typical feature of poetry and literature. But many familiar words and phrases have symbolic meanings, although we do not usually realize this when we use them.

What is a metaphor?

Look at these three sentences:

  • She flew past me on her bicycle.

  • Turing was the father of the modern computer.

  • He gave me a cold look.

In all these sentences, the word in bold type is not used in its primary or literal meaning – it is used metaphorically.

A metaphor is a type of comparison: when you use a word or phrase metaphorically, you use a meaning that has developed from the literal meaning and has some of the same features. For example, if you say someone ‘flies past’ on a bicycle or in a car, they are not really flying through the air, but the speed of their movement reminds you of a plane or a bird. This is a normal part of the way word meanings develop, and when a word has several meanings, some of those meanings are usually metaphorical.

How do metaphors work?

Every metaphorical word or phrase contains a ‘key idea’. This is the connection or similarity between literal and metaphorical meanings.

Sometimes the same key idea is expressed in several different words and phrases.

For example, when we talk about illness, we often use words and phrases whose literal meanings are to do with fighting or war:

  • A good diet will help your body fight disease.

  • The virus attacks the immune system.

  • Jean died on Sunday after a long battle with cancer.

In this case, the key idea is that trying to recover from an illness is like fighting a war, and many of the words and phrases we use to talk about illness express this idea. Once we understand this key metaphorical idea, it is easier to understand (and remember) words and phrases used for talking about illness. This is why metaphor is so important.

‘Metaphors we live by’

Metaphor is so common that it is sometimes almost impossible to talk about particular topics in English without using metaphorical words. For example, many common English words referring to responsibilities are metaphorical. In this case, the key idea is that having responsibility is like carrying a load: the bigger the burden, the heavier the load:

  • I have to bear the responsibility for this.

  • The responsibility was weighing on my mind.

  • I don’t want to be a burden to you.

Even though we may not realize that we are speaking metaphorically, the basic metaphorical idea has influenced how a particular concept is expressed in English, affecting how English speakers think about it. Metaphors that provide us with ways of thinking and talking about things are called conceptual metaphors, and they are the subject of an important book, Metaphors We Live By, by George Lakoff and Mark Johnson. Many others have written about metaphor, but Lakoff and Johnson introduced the ideas that have influenced the Metaphor Boxes in Macmillan Dictionary.

Idioms and similes

Idioms often contain metaphorical ideas: for example, expressions like spill the beans and give someone a hand are metaphorical. Similes are very like metaphors. The difference is that they include words such as like or as, which make it clear that two things are being compared. For example, that man is an animal is a metaphor, but he behaves like an animal is a simile. We have included idioms and similes in the Metaphor Boxes if they show the same key idea as other words in the group.